We currently always send displayDidRefresh for subframes immediately, instead of waiting for the next DisplayLink update. We should be able to keep a set of remote frames that are ready, and send a displayDidRefresh for each of them when the next DisplayLink update happens.
<rdar://problem/114402070>
Pull request: https://github.com/WebKit/WebKit/pull/17036
Committed 267270@main (f754a3da5ae0): <https://commits.webkit.org/267270@main> Reviewed commits have been landed. Closing PR #17036 and removing active labels.